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IsSimple - Has the Mapping been simplified?

Description:
This attribute indicates whether a Mapping has been simplified by the astSimplify method. If the IsSimple value is non-zero, then the Mapping has been simplified and so there is nothing to be gained by simplifying it again. Indeed, the astSimplify method will immediately return the Mapping unchanged if the IsSimple attribute indicates that the Mapping has already been simplified.
Type:
Integer (boolean), read-only.
Class Applicability:
Mapping
All Mappings have this attribute.
Frame
All classes of Frame return zero for the IsSimple attribute. This is because changes can be made to a Frame which affect the Mapping represented by the Frame, and so there can be no guarantee that the Mapping may not need re-simplifying. Most non-Frame Mappings, on the other hand, are immutable and so when they are simplified it is certain that they weill remain in a simple state.


next up previous 264
Next: Iwc - Include a Frame representing FITS-WCS intermediate world coordinates?
Up: AST Attribute Descriptions
Previous: IsLonAxis(axis) - Is the specified celestial axis a longitude axis?

AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 211
R.F. Warren-Smith & D.S. Berry
24th May 2011
E-mail:ussc@star.rl.ac.uk

Copyright (C) 2009 Science \& Technology Facilities Council